Tilt-cab truck cabs are in some cases attached to their chassis by shock absorber and spring assemblies which permit relative movement of the cab and the chassis as the truck moves over the road. When the cab is tilted relative to the chassis for maintenance or the like, the shock absorber and spring assemblies remote from the tilting axis are normally released from one or the other of those two components and are not involved in the tilting operation. However, the shock absorber and spring assemblies adjacent to the tilting axis normally remain "on line." Since the release of the other shock absorbers and spring assemblies and the pivoting of the cab places the entire weight of the cab on the shock absorber and spring assemblies adjacent to the tilting axis, there is a tendency for the assemblies to "fall through" their stroke. Such an uncontrolled fall can result in damage both to the cab and to components fixed to the chassis, such as the radiator.